Novel inductor circuit and wireless communication devices

ABSTRACT

An inductor circuit includes first inductive circuit, second inductive circuit, and third inductive circuit. First inductive circuit at receiver side has a first end coupled to a first port of an antenna and a second end coupled to an input port of a receiving circuit. Second inductive circuit at transmitter side has a first end and a second end respectively coupled to output ports of a power amplifier. Third inductive circuit at antenna side has a first end coupled to a first port of the antenna and having a second end. Second inductive circuit and the third inductive circuit are disposed on an outer ring to form a ring shape and the third inductive circuit is disposed on an inner ring within the outer ring to form a spiral shape. Third inductive circuit is disposed between the second inductive circuit and the first inductive circuit.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority of U.S. provisional application Ser.No. 62/701,852 filed on 2018 Jul. 23, which is entirely incorporatedherein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The invention relates to a wireless communication mechanism, and moreparticularly to a novel inductor circuit and corresponding wirelesscommunication devices.

2. Description of the Prior Art

Generally speaking, a conventional method or wireless device is arrangedto place an inductor at transmitter side (i.e. TX inductor) and adifferent inductor at receiver side (i.e. RX inductor) separately. Forexample, the TX inductor and the RX inductor are respectivelyimplemented on two different circuit chip dies. The disadvantage is thatsuch conventional arrangement takes up more circuit space. In addition,the performance of transmitter/receiver may be degraded.

SUMMARY OF THE INVENTION

Therefore one of the objectives of the invention is to provide a novelinductor circuit such as a novel trifilar component and wirelesscommunication devices, to solve the above-mentioned problems.

According to embodiments of the invention, an inductor circuit isdisclosed. The inductor circuit comprises a first inductive circuit, asecond inductive circuit, and a third inductive circuit. The firstinductive circuit at a receiver side has a first end coupled to a firstport of an antenna and a second end coupled to an input port of areceiving circuit. The second inductive circuit at a transmitter sidehas a first end and a second end respectively coupled to output ports ofa power amplifier. The third inductive circuit at an antenna side has afirst end coupled to a first port of the antenna and having a secondend. The second inductive circuit and the third inductive circuit aredisposed on an outer ring to form a ring shape and the third inductivecircuit is disposed on an inner ring within the outer ring to form aspiral shape. The third inductive circuit is disposed between the secondinductive circuit and the first inductive circuit.

According to the embodiments, a wireless communication device isdisclosed. The wireless communication device comprises a first inductivecircuit, a second inductive circuit, a third inductive circuit, and afirst capacitor. The first inductive circuit at a receiver side has afirst end coupled to a first port of an antenna and a second end coupledto an input port of a receiving circuit. The second inductive circuit ata transmitter side has a first end and a second end respectively coupledto output ports of a power amplifier. The third inductive circuit at anantenna side has a first end coupled to a first port of the antenna andhaving a second end. The first capacitor at the receiver side has afirst end coupled to the first end of the first inductive circuit and asecond end coupled to the second end of the first inductive circuit. Thefirst switching circuit is disposed between the first capacitor and thefirst end of the first inductive circuit or between the first capacitorand the second end of the first inductive circuit.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a wireless communication device according to afirst embodiment of the invention.

FIG. 2 is a diagram of the device of FIG. 1 operating under thetransmitting mode.

FIG. 3 is a diagram of the device of FIG. 1 operating under thereceiving mode.

FIG. 4 is a diagram of a circuit layout example showing the inductivecircuits L1, L2, and L3 according to an embodiment of the invention.

DETAILED DESCRIPTION

The invention aims at providing a solution/architecture of ultra-lowsignal loss and switchable T/R (transmitter/receiver) combined trifilarcomponent for a communication standard such as Bluetooth communicationapplications. In addition, the provided solution/architecture disclosesthe T/R combined trifilar component with co-coiled technique. Aninductor circuit of the T/R combined trifilar component can implementedon a single circuit chip die to save die areas.

FIG. 1 is a diagram of a wireless communication device 100 according toa first embodiment of the invention. The wireless communication device100 comprises a power amplifier (PA) circuit 105, a trifilar component107, an RF front-end matching circuit 110, and a low noise amplifier(LNA) circuit 115. The wireless communication device 100 is furthercoupled to an antenna 120. The wireless communication device 100 can beoperative under a transmitting mode or a receiving mode. FIG. 2 is adiagram of the device 100 operating under the transmitting mode. FIG. 3is a diagram of the device 100 operating under the receiving mode.

The trifilar component 107 includes at least three inductive circuitsL1, L2 and L3 positioned in a receiver side, a transmitter side and anantenna side of the wireless communication device 100 respectively,wherein the inductive circuits L1, L2 and L3 could be wirings.

The PA circuit 105 for example is a differential PA which is arranged togenerate differential output signals at its output ports TXP and TXNaccording to an input signal which is formed by differential inputsignals. In other embodiment, the differential PA 105 can be arranged togenerate the differential output signals according to an input signalformed by a single-end signal.

The inductive circuit L2 provides an inductance positioned at thetransmitter side and includes two input terminals/ends which arerespectively coupled to the output ports of the differential PA 105 of atransmitter circuit and respectively used for receiving the differentialoutput signals of the differential PA 105. The first end EL2A of theinductive circuit L2 is coupled to the first differential output signalof the differential PA 105 at the output port TXP, and the second endEL2B of the inductive circuit L2 is coupled to the second differentialoutput signal of the differential PA 105 at the output port TXN.

The inductive circuit L3 provides an inductance positioned at theantenna side and includes two output terminals/ends in which a first endEL3A of inductive circuit L3 is coupled to the matching circuit 110 anda first port ANTP of the antenna 120 while a second end EL3B ofinductive circuit L3 is coupled to a second port ANTN of the antenna120, e.g. a ground level (but not limited). The polarity at the firstend EL2A of inductive circuit L2 is identical to the polarity at thefirst end EL3A of inductive circuit L3.

The matching circuit 110 comprises a switching circuit SW2, a capacitorC1, and a switching circuit SW1.

The inductive circuit L1 includes a first end EL1A coupled to the firstend EL3A of inductive circuit L3 and a second end EL1B coupled to aninput port RXN of the LNA circuit 115. For better performance, thepolarity at the first end EL1A of inductive circuit L1 is different fromthe polarity at the first end EL3A of inductive circuit L3.

The switching circuit SW1 and capacitor C1 are arranged to be coupledbetween the first end EL1A and the second end EL1B of the inductivecircuit L1. In this embodiment, the capacitor C1 at the receiver sidehas a first end coupled to the first end EL1A of inductive circuit L1and has a second end coupled to the second end EL1B of inductive circuitL1. In addition, the switching circuit SW1 is disposed between thecapacitor C1 and the second end EL1B of inductive circuit L1. However,this is not intended to be a limitation. In other embodiments, theswitching circuit SW1 such as a switch implemented using a switchingtransistor may be disposed between the capacitor C1 and the first endEL1A of inductive circuit L1.

The switching circuit SW2 is employed and arranged to be coupled betweenthe input port RXN of LNA circuit 115 and a ground level. The inductanceprovide by the inductive circuit L1 and the capacitor C1 can form aresonator to produce a high impedance so as to avoid signal couplingloss and for example improve the signal sensitivity up to 2 dB (but notlimited).

As shown by FIG. 2, during a transmitting mode of the wirelesscommunication device 100, the switching circuits SW1, and SW2 are turnedon to become closed, the capacitor C1 and inductive circuit L1 areconnected in parallel in this situation, and thus form a resonant cavitywhich produces a high impedance for the signal generated from thetrifilar component 107. Further, the switching circuit SW2 is closed todraw the input port RXN of LNA circuit 115 to the ground level.

Thus, the differential output signals of the different PA 105 passthrough the trifilar component 107 and are transmitted or transferred tothe antenna 120 with very low or no signal degradation. The signals atthe transmitter (TX) path (from the differential PA 105 to the antenna120) are not coupled to the receiver side since the high impedanceprovided by the capacitor C1 and inductive circuit L1. For example, thedifferential PA 105 can deliver 10 dBm RF signal power to the antenna120. However, this is merely used for illustration and not intended tobe a limitation.

As shown by FIG. 3, during a receiving mode of the device 100, all theswitching circuits SW1, and SW2 are turned off to become open, theinductive circuit L1 becomes an input matching component of the LNAcircuit 115 at the receiver side to achieve lowest noise figure. Forexample, the noise figure may be 3.7 dB (but not limited). The signalsat the receiver (RX) path (from the antenna 120 to the LNA circuit 115)are not coupled to the transmitter side. Compared to conventionalcircuit architecture, the proposed invention for example can get 2 dBimprovement.

Further, in other embodiments, to save more chip die areas as well asachieve the above-mentioned designs of inductive circuits, the inductivecircuits L1, L2, and L3 are arranged to be positioned on a singlecircuit chip die to form an inductor circuit by adopting a novel circuitarchitecture/arrangement. FIG. 4 is a diagram of a physical circuitlayout example showing the inductive circuits L1, L2, and L3 accordingto an embodiment of the invention.

The inductive circuits L1, L2, and L3 comprised by such inductor circuitare disposed on a single circuit chip die area, i.e. in one plane, tosave chip area. This circuit architecture/arrangement includes an innerring and an outer ring. The inductive circuit L1 at the receiverside/path is disposed on the inner ring, and the inductive circuit L1 isformed as a spiral shape as shown by FIG. 4. The inductive circuit L1 atthe receiver path has two ends in which the second end EL1B is connectedto the input port RXN of the LNA circuit 115 and the first end EL1A isconnected to the first end EL3A of inductive circuit L3 and thenconnected to the first port ANTP of antenna 120. However, it should benoted that the physical circuit layout shown in FIG. 4 may beimplemented in a different circuit structure of another communicationdevice and is not limited to the circuit structure of communicationdevice 100. That is, it is not necessary to implement the physicalcircuit layout of FIG. 4 in the circuit structure of communicationdevice 100 of FIG. 1, and the circuit structure of communication device100 of FIG. 1 is not necessary to be implemented by the physical circuitlayout of FIG.

The plane may comprise two metal levels/layers (top layer and bottomlater) and utilize vias (electrical connections between layers in aphysical electrical circuit that goes through the plane of one or moreadjacent layers) to connect the two levels/layers. For example, thesecond end EL1B of inductive circuit L1 goes through a via of the bottomlayer to connect the port RXN, and the first end EL1A of inductivecircuit L1 goes through another via of the bottom layer to connect thefirst end EL3A of inductive circuit L3. Also, the first end EL3A ofinductive circuit L3 is connected to the port ANTP through a via of thebottom layer, and the second end EL3B of inductive circuit L3 isconnected to the port ANTN through another via of the bottom layer, asshown in FIG. 4.

The inductive circuits L2 and L3 are disposed on the outer ring to forma ring shape. The ring shape has two circles in which the inductivecircuit L3 is positioned or disposed on the inner circle while theinductive circuit L2 is positioned or disposed on the outer circle. Theinner circle is closed to the outer circle as shown by FIG. 4. Inpractice, each circle is arranged by an interlaced circuit structure.For example, the outer circle of inductive circuit L2 has two or moreoctagon/polygon/circular wires in which an inner wire may be connected,radially interlaced, and extended to an outer wire (as marked by 505shown in FIG. 4).

The interlaced circuit structure 505 shows that an end of the innercircle of inductive circuit L2 is extended and connected to an end ofits outer circle via a lower level such as the bottom layer whileanother end of the outer circle of inductive circuit L2 is extended andconnected to another end of its inner circle via a upper level such asthe top layer. From the top view of FIG. 4, the interlaced circuitstructure 505 indicates a cross connection. In addition, the interlacedcircuit structure 510 also shows that an end of the inner circle ofinductive circuit L3 is extended and connected to an end of its outercircle via a lower level such as the bottom layer while another end ofthe inner circle of inductive circuit L3 is extended and connected toanother end of its outer circle via a upper level such as the top layer.From the top view of FIG. 4, the interlaced circuit structure 510 alsoindicates a cross connection.

For the port TXP, the signal path for example may start from the portTXP, goes through the outer circle of inductive circuit L2, theinterlaced circuit structure 505, and the inner circle of inductivecircuit L2, and finally ends at the port TXN. In addition, the innercircle of inductive circuit L3 also has two or moreoctagon/polygon/circular wires in which an inner wire may be connected,radially interlaced, and extended to an outer wire (as marked by 510shown in FIG. 4). For instance, for the port ANTP, the signal path maystart from the port ANTP, goes through the inner circle of inductivecircuit L3, the interlaced circuit structure 510, and the outer circleof inductive circuit L3, and finally ends at the port ANTN. That is,each circle of inductive circuits L2 and L3 is not formed as a spiralshape.

Further, it should be noted that the inductive circuit L1 has multipleoctagon/polygon/circular wires which are formed as a spiral shape andare connected and extended without a radially interlaced structure. Theinductive circuit L1 for example is located in an upper level. The firstend EL1A is in the inner end and the second end EL1B is in the outerend. The first end EL1A is connected to the first end EL3A through apath in the lower level under the wires of the inductive circuit L1.From the top view of FIG. 4, the wires of inductive circuit L1 are crossover the path between the first end EL1A and first end EL3A. The secondend EL1B is connected to the RXN port through a path in the lower levelunder the wires of the inductive circuit L2 and wires of the inductivecircuit L3. From the top view of FIG. 4, the wires of the inductivecircuit L2 and wires of the inductive circuit L3 are cross over the pathbetween the second end EL1B and RXN port.

Additionally, the inductive direction of the inductive circuit L2 isdifferent from the inductive direction of inductive circuit L3. Forexample, the inductive direction of inductive circuit L2 may beclockwise, and the inductive direction of inductive circuit L3 may becounterclockwise.

During the transmitting mode of wireless communication device 100, asignal current may be generated at the first end EL2A of inductivecircuit L2, i.e. the first port TXP of differential PA 105, and thensequentially flows or passes through the upper half of the outerwire/trace of inductive circuit L2, a top layer of the interlacedcircuit structure 505, the bottom half of the inner wire/trace ofinductive circuit L2, the upper half of the inner wire/trace ofinductive circuit L2, a bottom layer of the interlaced circuit structure505, and bottom half of the outer wire/trace of inductive circuit L2,and the second end EL2B of inductive circuit L2, i.e. the second portTXN of differential PA 105, sequentially. That is, theinductive/signal/current direction is counterclockwise. In thissituation, the inductive direction of inductive circuit L3 is configuredto be clockwise which is opposite to that of inductive circuit L2. Forexample, in response to such signal current generated at the first endEL2A of inductive circuit L2, an inductive current may generated at thefirst end EL3A of inductive circuit L3 and then transmitted or outputtedto the first port ANTP of antenna 120. Thus, the inductive currentdirection/path sequentially pass through the second end EL3B ofinductive circuit L3, the upper half of the inner wire/trace ofinductive circuit L3, a top layer of the interlaced circuit structure510, the bottom half of the outer wire/trace of inductive circuit L3,the upper half of the outer wire/trace of inductive circuit L3, a bottomlayer of the interlaced circuit structure 510, and bottom half of theinner wire/trace of inductive circuit L3, and the first end EL3A ofinductive circuit L3.

In addition, during the receiving mode of wireless communication device100, the inductive direction of inductive circuit L3 is different fromthe inductive direction of inductive circuit L1. For example, if asignal current received at the first port ANTP of antenna 120, theinductive path/direction of inductive circuit L3 from its first end EL3Ato its second end EL3B is counterclockwise while the inductivepath/direction of inductive circuit L1 from its first end EL1A to itssecond end EL1B and then to the input port RXN of LNA circuit 115 isclockwise.

Further, the circuit distance between the outer ring and the inner ringis larger than the circuit distance between the outer circle and innercircle on the outer ring. That is, the space/circuit distance W1 betweenthe outer wire of inductive circuit L1 and the inner wire of inductivecircuit L3 is configured to be larger than the space/circuit distance W2between the outer wire of inductive circuit L3 and the inner wire ofinductive circuit L2.

In addition, equivalently the first end EL1A of inductive circuit L1 canbe regarded as an external connector of the spiral shape which isarranged to be coupled to the first end EL3A of inductive circuit L3.

In addition, for the implementation of this embodiment (but notlimited), the inductive circuit L1 from the first end EL1A to the secondend EL1B is implemented by using a metal trace which is wound around ina clockwise direction, and the inductive circuit L3 from the first endEL3A to the second end EL3B is implemented by using a metal trace whichis wound around in a counterclockwise direction while the inductivecircuit L2 from the first end EL2A to the second end EL2B is implementedby using a metal trace which is wound around in the counterclockwisedirection. However, this is not intended to be a limitation. In otherembodiments, the metal trace of inductive circuit L1 may be wound aroundin the counterclockwise direction, and the metal traces of inductivecircuits L2 and L3 may be wound around in the opposite direction, i.e.the clockwise direction. This also obeys the spirit of the invention.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

1. An inductor circuit, comprising: a first inductive circuit at areceiver side, having a first end coupled to a first port of an antennaand a second end coupled to an input port of a receiving circuit; asecond inductive circuit at a transmitter side, having a first end and asecond end respectively coupled to output ports of a power amplifier;and a third inductive circuit at an antenna side, having a first endcoupled to a first port of the antenna and having a second end; whereinthe second inductive circuit and the third inductive circuit aredisposed on an outer ring to form a ring shape and the third inductivecircuit is disposed on an inner ring within the outer ring to form aspiral shape; and, the third inductive circuit is disposed between thesecond inductive circuit and the first inductive circuit.
 2. Theinductor circuit of claim 1, wherein the inductor circuit includes atleast a top layer and a bottom layer.
 3. The inductor circuit of claim2, wherein each of the second conductive circuit and the thirdconductive circuit comprises an inner wire and an outer wire, andwherein the inner wire and the outer wire are disposed on the top layer,and the inner wire is connected, partially and radially interlaced, andthen extended to the outer wire through the bottom layer.
 4. Theinductor circuit of claim 3, wherein a space distance between an outerwire of the first inductive circuit and the inner wire of the thirdinductive circuit on the outer ring is larger than a space distancebetween the inner wire of the second inductive circuit and the outerwire of the third inductive circuit.
 5. The inductor circuit of claim 2,wherein the first end of the first inductive circuit is in an inner endof the spiral shape and is arranged to connect the first end of thethird inductive circuit through the bottom layer.
 6. The inductorcircuit of claim 1, wherein the first inductive circuit, the secondinductive circuit, and the third inductive circuit are disposed within asingle chip die.
 7. The inductor circuit of claim 1, wherein acurrent/signal inductive direction of the first inductive circuit isopposite to a current/signal inductive direction of the third inductivecircuit during a receiving mode.
 8. The inductor circuit of claim 7,wherein the current/signal inductive direction of the third inductivecircuit is a counterclockwise direction, and the current/signalinductive direction of the first inductive circuit is a clockwisedirection; and, the current/signal inductive direction of the secondinductive circuit is identical to the current/signal inductive directionof the third inductive circuit.
 9. The inductor circuit of claim 1,wherein each of the ring shape and the spiral shape is formed in a shapeof an octagon, a polygon, or a circle.
 10. The inductor circuit of claim1, wherein the second end of the third inductive circuit is coupled to asecond port of the antenna. 11-18. (canceled)